order, as well as economic well-being, can be found in the writings of ancient Chinese scholars, Plato, Aristotle, Ibn Khaldun, the physiocrats, the mercantilists, the classical school of economics, and, of course, Malthus. As one writer commenting on theories of political demography noted, "the thesis that excessive growth of population may reduce output per worker, depress the living of the masses, and engender strife is of great antiquity" (1).
Plato, for example, gave attention to the issue of population size as a consideration in the establishment of constitutional government and stable authority. Aristotle, with his concern for the conditions under which forms of government are transformed, considered the relation of population growth to an increase in poverty and hence civil discord. Rousseau, who also considered the relationship between population size and forms of government, concluded that direct popular government was possible only in small countries. And Mill, seeking a rational basis for challenging the argument that democratic forms were not possible in large countries, developed the theory and principles of representation.
Population growth and population movement were of explicit concern to Thomas Jefferson. Jefferson's belief in the special qualities of agrarian life was related to his conviction that there was an association between population density and the form and quality of civic life. Jefferson was also among the few theorists to give attention to the issues of immigration, which he did as part of his concern with the notion of fundamental and inalienable individual rights. Jefferson argued that there existed a "natural right which all men have of relinquishing the country in which birth or other accident may have thrown them, and seeking sustenance and happiness wheresoever they may be able to find them."* Jefferson's view, which runs so contrary to notions of patriotism based upon place of birth, was an important element in American immigration policy throughout its history.
But although a number of social and political theorists gave attention to the effects of population change in the past, it has only been in the last few decades that the issue has become a part of public discourse. Today, rapid population growth has become a popular explanation for many disturbing features of both the developed and developing world. Urban violence, political instability, crime, poverty, communism, and air pollution have all been related to the growth of population.
Concern with Population Decline
It is, therefore, particularly difficult for us to realize that only 30 years ago European scholars and statesmen were concerned with the social, economic, and political consequences of population decline. Myrdal, in his Godkin lectures at Harvard in 1938, focusing on the consequences of a de-
*Quoted in (2).